<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>块行区别</title>
</head>
<body>
<div>第一行</div>
<div>第二行</div>
<div>第san行</div>
<div>第si行</div>
<span>第一行</span>
<span>第二行</span>
<span>第san行</span>
<span>第si行</span>
</body>
</html>